1. Technical Field
The present invention relates to a vibration element, a vibrator, a vibration device, an electronic device and a moving object.
2. Related Art
Hitherto, as a vibration element for detecting an angular velocity, a vibration element disclosed in JP-A-2006-201011 has been known. The vibration element disclosed in JP-A-2006-201011 includes a basal portion, first and second detection arms extending out from the basal portion along both sides in a Y-axis direction, first and second coupling arms extending out from the basal portion to both sides in an X-axis direction, first and second drive arms extending out from the first coupling arm to both sides in the Y-axis direction, and third and fourth drive arms extending out from the second coupling arm to both sides in the Y-axis direction. In the vibration element having such a configuration, when an angular velocity around an Z-axis is applied in a state where each drive arm is vibrated in a drive mode, vibration in a detection mode is excited in the first and second detection arms, and thus an angular velocity can be detected from a signal which is obtained by the vibration in the detection mode.
Further, the vibration element disclosed in JP-A-2006-201011 includes a support portion that supports the basal portion, and four beams (suspension arms) that couples the basal portion to the support portion, and is configured such that each of the beams is inclined with respect to the X-axis direction and the Y-axis direction and extends out linearly (also see JP-A-2006-201053 and JP-A-2009-74996).
In the vibration element having such a configuration, the concentration of stress on a boundary portion between the basal portion and the beam is reduced, and thus it is possible to improve mechanical strength (impact resistance) in the boundary portion. However, since each beam is formed in a linear shape, a sufficient length is not able to be secured, and thus it is difficult to sufficiently absorb and relax an impact in each beam. As a result, the vibration element disclosed in JP-A-2006-201011, JP-A-2006-201053, and JP-A-2009-74996 has a problem in that mechanical strength (particularly, impact resistance at the time of falling) is not sufficient.